Planet Vocadulary Flashcards
Orbit
the circular path of an object as it revolves around another object.
Solar system
a system of objects that revolve around a star.
Galaxy
a group of solar systems, dust, and gas held together by gravity; our solar system is part of the Milky Way galaxy
Universe
everything that exists in, on and around the Earth
Satellite
an artificial body placed in orbit around the earth or moon or another planet in order to collect information or for communication.
Impact crater
a crater on a planet or moon caused by the impact of a meteorite or other object, typically circular with a raised rim.
Rotation
turning around on an axis; spinning
Revolution
an instance of revolving.
Season
a period of the year determined by the position of Earth as it revolves around the sun
Equinox
the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length (about September 22 and March 20).
Solstice
either of the two times in the year, the summer solstice and the winter solstice, when the sun reaches its highest or lowest point in the sky at noon, marked by the longest and shortest days.
Mare
are large, dark, basaltic plains on Earth’s Moon, formed by ancient volcanic eruptions
Eclipse
an event that happens when the shadow of an object in space falls on the surface of another object
Umbra
the fully shaded inner region of a shadow cast by an opaque object, especially the area on the earth or moon experiencing the total phase of an eclipse.
Penumbra
the partially shaded outer region of the shadow cast by an opaque object.